Architecture setup PVE, PBS

[Gregor]

Hello,

i own a mini server with the following specs:

• ASRock J5040-ITX (Gemini-Lake Refresh, Quad-Core, up to 3.2 GHz)
  • 4 x SATA
  • 1 x PCIe 2.0 (already used for second ethernet port)
• 1 x 500GB SSD
• 1 x 6TB HDD

Also i own a QNAP TS-253A with 16GB RAM and 1 x 6TB HDD.

Currently Proxmox VE is installed on the mini server on SSD. On the same SSD all LXC Containers store their system files. The HDD on the Mini-Server is used for LXCs data (e.g. Nextcloud data.) The HDD is setup as a ZFS pool, the SSD as lvm-thin.

On the QNAP i am running Proxmox Backup Server in a virtual machine with 12GB RAM and the HDD partitioned on QNAP as 2 disks. One 'disk' is used by Proxmox BS as lvm-thin for the system files, the other is setup as a ZFS pool to store backup data.

My Proxmox VE is configured to backup all LXCs, incl. HDD data, to the Proxmox BS. After having some performance issues backing up and restoring large LCXs (e.g. Nextcloud) I did some research on my bottlenecks. It seems, that ZFS on the PBS is very slow because I am not using a special device. Thus, the question is, how I can go around this issue:

• Should I use lvm on the PBS for the backup data? If so, should I change the HDD on the PVE also to lvm? What would be the downsides with my setup?
• As I have one HDD slot unused in my QNAP should I buy the QNAP Dual M.2 SATA SSD to 2.5" SATA RAID Adapter to be used as a hardware raid1 to set up a special device? In this case the risk of loosing the ZFS data only happens when both SSDs or the HDD break.

Is it necessary to set up a special device on the mini server, too? Or should I step away from ZFS with this setup?

Thank you very much for your help!

BR

Gregor